Lutathera for Treatment of Recurrent or Progressive High-Grade CNS Tumors

This study tests a radioactive drug called Lutathera in children, teens, and young adults (up to age 39) with high-grade brain tumors (such as glioblastoma) or meningioma that have come back or stopped responding to standard treatment. Lutathera targets tumors that have a specific protein on their surface, delivering radiation directly to cancer cells. **You may be eligible if...** - You are between 4 and 39 years old (age range varies by study phase) - You have a high-grade brain tumor or meningioma that has recurred or not responded to standard therapy - Your tumor shows uptake on a special scan (DOTATATE PET), confirming it has the target protein - Your overall health and organ function are good enough to tolerate treatment **You may NOT be eligible if...** - Your cancer has spread to the bone marrow - You have a very large tumor causing dangerous brain swelling - You have type 1 diabetes - You are breastfeeding - You are currently receiving other anti-cancer treatments Talk to your doctor to see if this trial is right for you.